Ghost and Acronis are very pricey, many admins use the two software packages in an illegal way. If you aren't paying roughly $30-$50 per PC then you are probably using it illegally. This is a great way to get the same functionality if not more and be legit.
This is a beginners guide to Clonezilla live. Clonezilla is an open source clone system based on debian, It has the same look and feel as Norton Ghost. In this example we will use the Ubuntu version. All you need is a File Server with NTFS and the Clonezilla ISO and you will be able to image a PC across the network in no time. I have created this How-to with the windows admin in mind. Linux geeks can skip this guide, there is a wonderful CLI to script everything with.
For those of you in a SMB setting you may want to consider FOG instead, it allows multicasting and image management via a PXE environment. It is better suited to your needs. But for a single PC clone situation this is a great way to do it.
Check the FOG how-to here: http://community.spiceworks.com/how_to/show/373

4 Steps total

Step 1: Get Clonezilla Live

Step 2: Set up a Share

I like to image to a share for simplicity I don't want to carry around a USB drive everywhere and fight with it. So in this example we are going to create a share called 'images' and set permissions.
1. Log onto a server, in this case it will be 'BACKUPSERVER'
2. Create Folder named 'Images'
3. Share the folder as Images
4. Set permissions appropriately, in my case I will just let the domain administrator use the share. You may use whatever you want. Just remember it as you will need these credentials later.

NOTE:
Just make sure that the fileserver you use has enough space to save the images to. I would also suggest using a NTFS partition as Fat32 doesn't play nice with big files.

Step 3: Boot from Clonezilla

Put the Clonezilla CD you created in step 1 in the drive of the PC that needs cloned change the boot order to boot to CD.

1. A bunch of text will go by then a splash screen will come up. Just hit Enter.
2. At the Language screen, select English or your preferred language. Enter
3. Don't Touch Keymap, enter
4. Start Clonezilla! Enter

Step 4: Clone!

In this example we are going to start easy with a device-image. Meaning the information cloned will be saved to a neatly wrapped up image on the share we created earlier.

1. Device-image. Enter.
2. Samba_Server. Enter (We will Use SAMBA as this allows us to access windows file shares.)
3. DHCP (whatever is necessary on your LAN). Enter
4. Enter the name of the server from step 2. BACKUPSERVER enter.
5. Enter domain domain.tld Enter.
6. Since I used domain admin I will leave 'Administrator' for the share permissions. Enter.
7. Since I used Images as my share, I will leave this as default. Enter.
8. Enter
9. Enter the password at the bottom of the screen for the Administrator.
10. You will see \\BACKUPSERVER\Images at the bottom of the list if authentication was successful. Enter.
11. Beginner Mode.
12. Here is where you get to choose to restore an image or save a new one, the steps are the same. but for our example lets select 'savedisk' Enter
13. Give the image a descriptive name, I like to keep the date and the name of the model of PC. Enter
14. Make sure you are backing up the correct disk in case there are multiple on the local system. Hit Enter.
15. It may be useful to note the command in green if you want to avoid using the GUI next time. Enter
16. Verify information in yellow. then hit 'y' Enter
17 you will get a status report on the progress. On my network we run about 500-900MB/min just so you have a benchmark.

When done eject the disk and check the file share to see your image. Just remember, with linux you will be unable to eject your disk until AFTER you shutdown...

You now have a snapshot of your image that you can restore at any time. You restore using the exact same process but on step 5 part 12 you just select restore image instead.
Important notes!
If you are going to deploy this image to multiple PCs, remember you SHOULD to sysprep a windows install BEFORE you clone. Otherwise you will create a lot of havoc on your network with Identifiers being duplicated. This will manifest in WSUS servers not detecting your PC properly, and some pcs being unable to accomplish certain tasks.
Make sure your firewall allows traffic through to the server or you will error out.
You can multicast with clonezilla server, meaning you can take a single image and push it to as many PCs as you want from your desk. Ahhh laziness :) I will work on that how-to next.

Hey, you say jump I say how much beer do you want..:) Ironically in another thread someone was talking about the cost of ghost, and another user mentioned FOG, I am gonna try it now it is looking amazing. Clonezilla seems to have the corner on single PC restores, FOG seems to be golden on the multicasting, supposedly you can do it from an iphone...

Ya, keys are always a pain. someday I hope MS will take pitty on the businesses who like to image and have OEM licenses.
If you like this check out my FOG how-to, it is more suited for business networks.